WX and turbulence encounter results in altitude and course deviation near lga, ny.

Attributes
ACN	475814
Time
Date	200006
Day	Sun
Local Time Of Day	0601 To 1200
Place
Locale Reference	navaid : lga.vor
State Reference	NY
Altitude	msl bound lower : 2700 msl bound upper : 3000
Environment
Weather Elements	Turbulence
Light	Daylight
Aircraft 1
Controlling Facilities	tracon : n90.tracon
Operator	common carrier : air carrier
Make Model Name	MD-80 Super 80
Operating Under FAR Part	Part 121
Navigation In Use	other vortac
Flight Phase	descent : approach
Route In Use	arrival : on vectors
Flight Plan	IFR
Aircraft 2
Controlling Facilities	tracon : n90.tracon
Operator	Other
Make Model Name	Any Unknown or Unlisted Aircraft Manufacturer
Flight Phase	cruise : level
Person 1
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : instrument pilot : commercial pilot : multi engine
ASRS Report	475814
Person 2
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
ASRS Report	475815
Events
Anomaly	altitude deviation : excursion from assigned altitude conflict : airborne less severe inflight encounter : weather inflight encounter : turbulence inflight encounter other non adherence : clearance other anomaly other other spatial deviation
Independent Detector	other flight crewa other flight crewb
Resolutory Action	controller : issued new clearance flight crew : regained aircraft control flight crew : exited adverse environment
Consequence	faa : reviewed incident with flight crew
Supplementary
Problem Areas	ATC Human Performance Flight Crew Human Performance Weather
Primary Problem	Weather

Narrative:

While being radar vectored for approach at 3000 ft, we encountered windshear that resulted in an increase of airspeed of +50 KTS followed by loss of 20 KTS. We executed an escape maneuver while holding our assigned altitude and airspeed. Moderate to severe turbulence was also encountered. We elected to fly in a direction that would take us away from the WX. This was contradictory to ATC request. But safety to the aircraft required us to exit the area as soon as possible. During maneuvering, a traffic conflict was presented. We were able to sight the traffic and maintain visual separation. At this time we were issued a heading and attempted to comply. During the turn, a downdraft was encountered. The autoplt was not able to hold altitude and subsequently lost 300 ft. The autoplt was disengaged and the altitude was regained manually. During this time, lga changed arrival runways. We were issued vectors for the approach to runway 31. While on descent, the WX and turbulence improved and a safe approach and landing were made. Supplemental information from acn 475815: after landing, called N90. Informed supervisor of what happened. He said there was no loss of separation and no problem. He would pass information to controller. Lesson learned: even with routine landings occurring in visibility conditions over the field, severe weather in a high density environment can quickly cause task saturation on both sides.

Original NASA ASRS Text

Title: WX AND TURB ENCOUNTER RESULTS IN ALT AND COURSE DEV NEAR LGA, NY.

Narrative: WHILE BEING RADAR VECTORED FOR APCH AT 3000 FT, WE ENCOUNTERED WINDSHEAR THAT RESULTED IN AN INCREASE OF AIRSPD OF +50 KTS FOLLOWED BY LOSS OF 20 KTS. WE EXECUTED AN ESCAPE MANEUVER WHILE HOLDING OUR ASSIGNED ALT AND AIRSPD. MODERATE TO SEVERE TURB WAS ALSO ENCOUNTERED. WE ELECTED TO FLY IN A DIRECTION THAT WOULD TAKE US AWAY FROM THE WX. THIS WAS CONTRADICTORY TO ATC REQUEST. BUT SAFETY TO THE ACFT REQUIRED US TO EXIT THE AREA ASAP. DURING MANEUVERING, A TFC CONFLICT WAS PRESENTED. WE WERE ABLE TO SIGHT THE TFC AND MAINTAIN VISUAL SEPARATION. AT THIS TIME WE WERE ISSUED A HDG AND ATTEMPTED TO COMPLY. DURING THE TURN, A DOWNDRAFT WAS ENCOUNTERED. THE AUTOPLT WAS NOT ABLE TO HOLD ALT AND SUBSEQUENTLY LOST 300 FT. THE AUTOPLT WAS DISENGAGED AND THE ALT WAS REGAINED MANUALLY. DURING THIS TIME, LGA CHANGED ARR RWYS. WE WERE ISSUED VECTORS FOR THE APCH TO RWY 31. WHILE ON DSCNT, THE WX AND TURB IMPROVED AND A SAFE APCH AND LNDG WERE MADE. SUPPLEMENTAL INFO FROM ACN 475815: AFTER LANDING, CALLED N90. INFORMED SUPERVISOR OF WHAT HAPPENED. HE SAID THERE WAS NO LOSS OF SEPARATION AND NO PROB. HE WOULD PASS INFO TO CONTROLLER. LESSON LEARNED: EVEN WITH ROUTINE LANDINGS OCCURRING IN VIS CONDITIONS OVER THE FIELD, SEVERE WEATHER IN A HIGH DENSITY ENVIRONMENT CAN QUICKLY CAUSE TASK SATURATION ON BOTH SIDES.

Data retrieved from NASA's ASRS site as of July 2007 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.